Cyclodextrins are well known ingredients for use in a variety of consumer products. Cyclodextrins are synthetic carbohydrates prepared from hydrolyzed starch by the action of cyclodextrin-glycosyl transferase, an enzyme obtainable from several organisms such as Bacillus macerans or related Bacillus strains. Cyclodextrins have a cyclic malto-oligosaccharide structure with 6 or more alpha-1,4-linked glucose units, the most common of which are alpha-cyclodextrin, beta-cyclodextrin, and gamma-cyclodextrin with 6, 7, and 8 linked glucose units, respectively.
Gamma-cyclodextrin, for example, can be characterized in terms of the following general structure:
Due to its unique structure, gamma-cyclodextrin is often used in pharmaceutical and nutritional products as a delivery vehicle for hydrophobic or poorly water-soluble molecules. The hydrophobic inner core of the cyclodextrin molecule complexes with organic or otherwise compatible molecules, while the hydrophophilic outer surface of the cyclodextrin molecule allows for the entire inclusion complex to dissolve in an aqueous medium. This application of the cyclodextrin inclusion complex has been found especially useful in protecting sensitive molecules such as vitamins, flavorants, and similar other materials from oxidation, evaporation, or other forms of degradation, as formulated into a variety of nutritional products.
Gamma-cyclodextrins are frequently described in the literature as being a rapidly digested carbohydrate, unlike their alpha and beta counterparts which are generally recognized as non-digestible. The rapidly digested gamma-cyclodextrin has been characterized as such based upon a number of studies, including in vitro incubations with human salivary and pancreatic amylases (Kondo H, Nakatani H, Hiromi K: In vitro action of human porcine α-anlyases on cyclo-malto-oligosaccharides, Carbohydrate Research 1990; 204:207-213) and good tolerance of single 8 g doses when fed to healthy adult subjects (Koutsou G A, Storey D M, Bar A: Gastrointestinal tolerance of cyclodextrins in humans, Food Add Contamin 1999; 16:313-317). It has thus been assumed that gamma-cyclodextrin is completely degraded in the human small intestine (Wacker Bicochem Corp., Digestion of parent cyclodextrins, Jan. 17, 2000).
It has now been found, however, that orally administered gamma-cyclodextrin results in a surprisingly blunted blood glucose curve in both human and animal models. This is especially surprising given that the literature reports gamma-cyclodextrin as rapidly digested and absorbed in the small intestine, which would then be expected to result in a relatively steep blood glucose spike following administration. On the contrary, we found that gamma-cyclodextrin provides a blunted postprandial glucose response, as well as reduced insulin secretion, more akin to that of a slowly digested carbohydrate rather than the rapidly digested carbohydrate that gamma-cyclodextrin has been reported in the literature to be. These new findings are based primarily upon a study involving male fatty Zucker fa/fa rats fed gamma cyclodextrin compared with a maltodextrin challenge, and a human study of healthy non-diabetic human subjects which corroborated the observations made in the rat study. Both studies are described hereinafter in greater detail.
It has also been found, based primarily upon the above-referenced data, that nutritional products can be formulated with gamma-cyclodextrin to provide diabetics or other suitable individuals with a nutrition source that delivers a blunted postprandial glycemic response. These products allow for better control over blood glucose fluctuations, both hyper- and hypoglycemic swings, after eating a meal or snack. This is especially useful in individuals prone to such glycemic swings, including those afflicted with various degrees of glucose intolerance such as insulin-dependent diabetes mellitus (IDDM) and non-insulin dependent diabetes mellitus (NIDDM).
It has also been found that the above-referenced products are useful in most any application where control of postprandial blood glucose is desirable, such as to control appetite by way of blood glucose control as described herein, and subsequent control over body weight management.
It is therefore an object of the present invention to provide a method of providing nutrition that also provides blood glucose control following administration of the nutrition. It is a further object of the present invention to provide diabetics or others with a method of obtaining nutrition and better postprandial blood glucose control. It is a further object of the present invention to provide a method of controlling appetite and managing body weight, by administering nutritional products that deliver a blunted blood glucose response following such administration. It is yet another object of the present invention to provide such methods using gamma-cyclodextrin, and further to provide such benefits through the administration of nutritional products containing gamma-cyclodextrin.